Ísafjörður–Suðureyri–Flateyri Tunnel The Westfjords

Completed in 1996, this 9km-long tunnel network beneath the mountains becomes an unusual one-lane tunnel in parts of the 6km stretch from Ísafjörður to Flateyri. In the middle of the mountain it branches, and a 3km section of tunnel shoots off to Suðureyri. Worry not: pull-outs throughout allow oncoming traffic to alternate as it rides through the damp chutes.